US Bridges

FM - Olive over Nishnabotna River

Poor

Cass County, Iowa · 077363302 · Structure no. 000000000101160

Built
1961
64 years old
Condition
Poor
inspected March 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
253 ft
3 main spans
Daily traffic
1,524
2022 count
Owner
County
County Highway Agency

About this bridge

FM - Olive over Nishnabotna River is a steel continuous stringer/multi-beam or girder carrying FM - Olive over Nishnabotna River in Cass County, Iowa. It was built in 1961, so it is 64 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 1,524 vehicles a day, roughly 13% of them trucks, projected to reach 1,524 by 2044. The structure is 253 ft (77.1 m) long and 33 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesFM - Olive
CrossesNishnabotna River
Location077363302
RouteCounty Highway 0
StateIowa
Coordinates41.43151, -95.00341
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating43.4 US tons
Inventory rating30 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length253 ft (77.1 m)
Longest span98 ft (29.9 m)
Deck width33 ft (10.1 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,524 (2022)
Projected traffic1,524 by 2044
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$3.8 million (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was FM - Olive over Nishnabotna River built?

It was built in 1961, making it 64 years old in 2025.

What condition is FM - Olive over Nishnabotna River in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in March 2024.

How much traffic does FM - Olive over Nishnabotna River carry?

About 1,524 vehicles per day (2022 count), of which roughly 13% are trucks.

How long is FM - Olive over Nishnabotna River?

The structure is 253 ft (77.1 m) long with a longest span of 98 ft (29.9 m) and a deck 33 ft wide.

Who owns FM - Olive over Nishnabotna River?

It is owned by the County Highway Agency.